Magnetic phase emergence in doped-twisted bilayer boron nitride

Abstract Twisted stacking of two-dimensional systems is changing our understanding of quantum phenomena, such as strongly correlated states and superconductivity. Exploring additional twisted bilayers can uncover phenomena and applications in the semiconductor industry. Band structure engineering, governed by the interlayer rotation angle, enables precise manipulation of material properties and exploration of emerging magnetic phases. Changing the rotation angle in twisted bilayer boron nitride leads to flat bands. Our first-principles calculations show that hole doping within these narrow bands induces electronic instability, resulting in a magnetic phase that relies heavily on the twist angle. As this angle decreases, a localized state appears at the valence band, altering the charge density required to trigger the magnetic phase. We investigate the electronic nature of these localized states and their implications for the magnetic properties. Our results show a magnetic phase that enhances spin polarization, which may contribute to spintronics research. These findings could be a factor in materials science and condensed matter physics.